تاثیر عدم قطعیت هدایت هیدرولیکی و تعداد نمونه در روش مونت کارلو بر تغییرات زمانی تحکیم خاک

نوع مقاله : مقاله پژوهشی

نویسندگان

1 عضو هیات علمی گروه مهندسی آب دانشگاه گیلان

2 دانشجوی دانشگاه گیلان

چکیده

نقش عدم­قطعیت هدایت هیدرولیکی به عنوان عاملی مؤثر در تحلیل احتمالاتی تحکیم خاک حائز اهمیت می­باشد. در تحقیق حاضر، برنامه­ای رایانه­ای در محیط MATLAB توسعه داده شد و پس از حل عددی معادله دیفرانسیل تحکیم به روش تفاضل محدود، از آن به عنوان راه­حل پایه، در شبیه­سازی مونت­کارلو استفاده گردید. همچنین تأثیر تعداد نمونه تصادفی در مدل احتمالاتی تحکیم به روش مونت­کارلو با کاربرد 100 و 1000 نمونه از توزیع­ لوگ-نرمال هدایت هیدرولیکی مربوط به زمینی در سراوان گیلان بررسی شد. نتایج نشان داد که با افزایش زمان، منحنی توزیع احتمالاتی فشار آب منفذی هموارتر و عدم­قطعیت بیش­تر می­گردد. افزایش تعداد نمونه هدایت هیدرولیکی از 100 نقطه به 1000 نقطه، تأثیر کمی بر توزیع احتمالاتی فشار آب منفذی نشان داد. همچنین بیش­ترین ضریب نیکویی برازش توزیع نرمال بر فشار آب منفذی در نزدیک به سطح خاک و 23 درصد بیش از مرکز لایه خاک به دست آمد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of uncertainty of hydraulic conductivity and number of samples in Monte-Carlo method on time-dependent variation of soil consolidation

نویسندگان [English]

  • Amir Malekpour 1
  • Nima Sadeghiyan 2
  • Mahtab Mohammadi 2
1 Academic staff, Dept. Water Engineering, University of Guilan
2 B.Sc. Student of University of Guilan
چکیده [English]

The uncertainty of hydraulic conductivity plays an important role in probabilistic analysis of consolidation of soils. In current research, a computer program was developed in MATLAB and solving the governing partial differential equation using numerical finite difference method, it was applied as the basis solution to Monte-Carlo simulation. Meanwhile, the effect of number of random samples was investigated applying 100 and 1000 samples from log-normal distribution of hydraulic conductivity (related to a land located in Saravan-Guilan) into the probabilistic consolidation model. The results showed that the probabilistic distribution curve of pore-water pressure becomes flatter with time and the uncertainty increases. Increasing the number of hydraulic conductivity samples from 100 to 1000 caused negligible effect on the probabilistic distribution of pore-water pressure. Moreover, the greatest goodness of fit of normal distribution to pore-water pressure obtained close to the soil surface and 23 percent greater than the center of soil layer.

کلیدواژه‌ها [English]

  • Fine-grained soil
  • Log-normal distribution
  • pore-water pressure
  • probabilistic analysis
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